Constructing Robust and Efficient Ionic Conductive Interfaces for Utilizing SiOx Anodes in Advanced Lithium-Ion Batteries with High Energy Density

Silicon monoxide (SiO_x) material is considered a promising contender for anodes in high-power lithium-ion batteries owing to its high specific capacity. Nevertheless, the substantial volume fluctuation during the lithiation/delithiation cycles of SiO_x anodes leads to reduced initial coulombic efficiency (ICE) and capacity retention, hindering its practical implementation. To tackle this challenge, researchers have pre-fabricated a sturdy ionic conductive interface abundant in LiF, Li₂C₂O₄, LiBO₂, and Li₂B₄O₇ via a calcination process. This interface layer, distinguished by its high Young's modulus and swift Li+ conductivity, can efficiently accommodate the plastic deformation of SiO_x anodes, curtail parasitic reactions, and preserve electrode integrity. The enhanced SiO_x (M-SiOx500°C) anode demonstrates improved ICE, superior capacity retention, and outstanding rate capability. A complete cell paired with a LiNi_0.8Mn_0.1Co_0.1O₂ cathode maintains a capacity level of 89.7% after 200 cycles. This study highlights the importance of pre-fabricating artificial solid-electrolyte interphase (SEI) layers and modifying interfacial chemistry to enhance the performance of SiO_x-based anodes, representing a notable step forward in the broad adoption of SiO_x-based anodes.